Numerical Investigation on Flow Characteristics in the Horizontal Elbow Suction Pipe Connected to Sumps of Large-Scale Pumping Stations

Abstract

Abstract To know the flow characteristics in the horizontal elbow suction pipe connected to sumps of large-scale pumping stations, the distribution of air-entraining vortex and water velocity is studied using ANSYS CFX with considering the gravity. The Volume of Fluid (VOF) method is adopted to track the water level of the sump. The results show that a typical funnel-shaped continuous air-entraining vortex is observed via the air volume fraction. Its size gradually increases from the inlet to outlet of the suction pipe. The pressure changes linearly with the water depth under the effect of gravity whereas the velocity shows non-uniform distribution. The axial velocity distribution of the outlet is non-uniform in the radial direction, which is analogous to the velocity distribution. In addition, the centre wall of the suction pipe outlet may affect remarkably the velocity distribution.